Engine starter



May 13, 1930.

W. L. M CGRATH ENGINE STARTER Filed Jan. 23, 1924 3 Sheets-Sheet l W. L. MCGRATH ENGINE STARTER v May 13, 1930.

-3 sheets-sheet 2 Filed Jan. 25

Inc/@afar May 13, 1930. w. L. MCGRATH ENGINE STARTER Filed Jan. 25, 1924 3 Sheets-Sheet 3 Mw@ A JW Patented May 1.3, 1930 UNLLTED STATES vPATEN'I ovl-Fica WILLIAM L. MCGRATBI, OF ELMIRA, NEW YORK, A SSIGNOR v'.lO ECLIPSE MACHINE COM- I PANY, OF ELMIRA, NEW YORK, CORPORATION F NEW YORK ENGINE STARTER Application filed January 23, 1924. Serial No. 688,077;

My invention has relation to means for starting or cranking an engine such as an internal combustion engine, and more particularly to that part thereof known as the drive or transmission which transmits the power of a prime mover such as an electric motor to a part or member of the engine to be started, such as the flywheel thereof. T heobject of my invention is to provide a simple and etlicient drive or transmission which is capable o f a manual operation for engagement with the engine member. My drive contains novel features of construction resulting in novel operations and results, which will be apparent from the description hereinafter given.

In the drawings,-F ig. 1 is a sectional elevation of an engine starter system includingr my new drive or transmission, the part being here illustrated in normal disengaged position; Fig. 2 a sectional elevation of the drive, illustrating the position of the parts under pinion abutting condition, with the driving member or pinion about to enter theV flywheel; Fig. 3 a

sectional elevation of the drive', illustrating the position of the parts during the cranking operation; F ig. 4 a sectional elevation of the drive proper; Figs. 5 and 6 sections on the corresponding section lines of Fig. 4; Fig. 7

a detail view artly in longitudinal section of the screw sha t; Fig. 8 a view of one end of the pinion; Fig. 9 a section" on the line 9--9 of Fig. 8 gFig. 10 a view of one end of the nut;

Fi 11 anelevation of the nut with a 'portion thereof broken away; Fig. 12 an elevation of the drum 14 alone; Fig. 13 an elevation of a substitute `or longv shifting sleeve; Fig. 14 a detail of the locking ring alone Fig. 15 an end elevation of the nut, drum and ring; and

16 an elevation of the nut and drum with the shell and ring in section.

For the purpose of a'clear and definite disclosure of my invention, have shown the same embodied in a certain specilic structure, but it will be understood that such invention maybe embodied in structures of somewhat different 4formation and arrangement without departing from the spirit and scope of my invention.` It will also. be vunderstood that while Ihave shown my invention as applied to the spo-called outboardtyp'eof drive, the

same Vmay be applied to the inboa'rd type ofdrive. Further, it will be Aunderstood that while I have shown my invention embodied in that type of drive known as thedirect drive, in which the drive is directly connected with.

the extended armature shaft of an electric motor, my invention is also applicable to the indirect drive in which the drive or transmission is connected with a countershaft driven by the armature shaft. y i

`Referring to the particular embodiment 4of my invent-ion as illustrated in the drawings, the prime mover is an electric motor 1 prolvided with an vextended armature shaft 2 and having a suitable switch and electrical connections lwhich are of the usualkind and therefore need not be illustrated.

Vso

The drive or transmission is formed as an assembly which is readily applicable to and detachable from the extended armature shaft 2. This drive assembly comprises, in the present instance, a shaft which is in the form of a sleeve 3 (shown separately in Fig. 7) and which is mounted upon the armaturevshaft for rotary movement therewith and longitudinal movement thereof through a suitable medium as for instance the series of splines 4 on the armature shaft with their intervening grooves a-nd the series of corresponding splines 5 and their intervening grooves in the bore of the v sleeve 3. To' one end of the sleeve 3 is secured,

as--by threading thereon, 'a stop nut 6 and at the other end, and also preferably by thread- `ing thereon a shifter sleeve 7. The sleeve 3 has a smooth surface portion 8 on which slides the driving member which ishere in the form of a pinion 9 and it is also provided' towards `one' end with coarse or .steep pitch screw threads 10 by which the actuating or control membery 11 is operatively connected with the screw shaft by being threaded thereto for longitudinal movement thereof and rotary movement therewith. i L' The control member 11, hereinafter called anut, is operatively connected with the pinion by g. means of a friction clutch whereby the torque ofthe startingmotor is transmitted from the screw shaft andl ,the nut to the pinion and thenceto the flywheel of the engine when the pinion is in cranking position. The clutch mechanism herein shown comprises two sets of clutch plates 12 and 13, the memberssof which alternate and which the friction plates in assembled position with respect to the pinion, a locking wire 18 is positioned in a circumferential groove 19 in the tongues 15, Figs. 4 and 9. Y

The drum 14 is secured to the nut l1 in a suitable manner as by means of the tongues 20 on the nut interitting with corresponding..

tongues 21 in the central bore of the drum,

with the projecting lip 20a riveted over into the recess 14a. However, as is obvious, the nut 11 and drum 14 may be made in one piece,

` if desired.

The friction clutch assembly is held together in a suitable manner as by means of the shell 22 having an outer radial flange fitting over the outermost friction plate and an inner flange within which is introduced a locking wire or ring 23 bearing against the drum 14. By preference a yielding pressure is exerted upon the nut 11 as by means of the coiled spring 24 interposed between its outer flange 25 and the shifter sleeve 7.

The drive assembly is adapted to be shifted manually or pedally and I will hereinafter refer to such action as a manual operation, using that term broadly to cover both operations. Any suitable manual shiftingmeans which is also .capable of operating the usual motor switch may be employed and in the present instance, I have shown a 'portion of such a means such as a lever 26 pivoted at 27.,

on the bracket 28 which is secured to the `motor frame and which also provides the bearing for the outer end of the armature shaft 2. The lower end of this lever 26 is made in the form of a yoke 29 terminating in rollers 30 which are positioned between the flanges 31 of shifting sleeve andare thereby operatively connected therewith.

Describing the cycle of operation of my' drive or transmission and beginning with the parts in their normal disengaged position shown in Fig. 1, the operator manuallyactuates the lever 26 whereupon the entire drive assembly isslid longitudinally along the armature shaft 2 by reason of the splined connection. In the event of perfect .register between the pinion teeth and the teeth of the flywheel, the pinion will go intofull mesh as illustrated in Fig. 3, at or about which time the starting motor is operatedby the closing of the switch connection either as a separate kmanual operation or as incidentally to the to initiate the above described screw action, inasmuch as it'maintains frictional'contact between the clutch plates, which frictional contact is thereafter automatically increased by the pressure due to the longitudinal component of the torque resistance transmitted through the screw threads, in accordance with the resistance of the flywheel so that a torque will be transmitted by the clutch sufficient to break loose the flywheel fr0mstationary position and to rotate it.

' When the engine starts on its own power and the flywheel rotates the pinion which now becomes the driven member, the screw jack action will be relieved and likewise the frictional resistance between the clutch plates due to such action will begrelieved, with the result that the When the operator relieves the pressure upon the lever 26 and assembly will be restored to normal position.' (in suitable manner, as by a spring 32) lthe pinion being thereupon disengaged from the flywheel. ,A

In 4the, event of abutting of the pinion teeth and the flywheel teeth, the` shifter sleeve"7 and consequently the screw shaftv will continue their longitudinal movement to the left, and, owing to the provision of the steep pinion lwill be driven freely. v

the shifting means, the drive pitch of screw thread, the pinion, whose longitudinal movement'has been arrested, will be rotated slightly and sufficiently to result in register between the teethcf the pinion and flywheel. The position ofthe parts at` this particular .stage is illustrated in Fig. 2.

-The pinion will thereupon move longitudnally with the mesh with the flywheel. g

While the shifting sleeve 7 may obviously be made integral with the screw'shaft, I prescrew shaft and go into full fer to make it as a separate piece attachable l thereto, in order that the drive assembly may be made standard for all installations which can be taken care of by making the sleeve portion-of this shifter 7 of the' desired length and diameter to accommodate the relative position of the shifting yoke 29 or the like. A sleeve 33 elongated for such purpose is shown in Fig. 13.

I prefer to make the locking ring as in Figs. A14 and 15., wherein it is shown as having au offset end or tail piece which presses. against ythe outer face ofthe drumffas illustrated inv Fig. 16. ThisI construction provides an efmounted on the shaft and adapted to engage a member of the engine to be started, a control member mounted on the shaft for longitudinal movement thereof and rotary movement therewith, and a friction clutch interposed between the control member and the driving member, said clutch comprising two sets of plates, one set being interlocked with the driving member, and the control member having a drum extension with which the other set of plates is interlocked.

1l. An engine starter drive including a rotatable' shaft mounted for longitudinal and rotary movements, a driving member loosely mounted on the shaft and adapted to engage a member of the engine to be started, a control member mounted on the shaft for longitudinal movement thereof and rotary movement therewith, and a friction clutch interposed between the control member and the driving member, said clutch comprising two sets of plates, one set being interlocked with the driving member, and the control member having a drum extension with which the other setof plates is interlocked, said extension encompassing said friction clutch.

12. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements, a driving member loosely mounted on the shaft and adapted to engage a member of the engine to be started, a control member mounted on the shaft for longitudinal movement thereof and rotary movement therewith. and a friction clutch interposed between the control member and the driving member, said clutch comprising two sets of plates, one set being interlocked with the driving member, and the control member having a drum extension with which the other set of plates is interlocked, and a shell fitting over the drum extension and having a flange to hold the clutch plates in position.

13. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements, a driving member loosely mounted on the shaft and adapted to engage a member of the engine to be started,a control member mounted on the shaft for longitudinal movement thereof. and rotary movement therewith, anda friction clutch interposed between the control member and the driving member, said clutch comprising two sets of plates, one setA being interlocked with the drivingV member, and the control member having a drum extension with which the other set of plates is interlocked, a shell fitting over the drum extension and having flanges at opposite ends, one flange holding the clutch plates in position, and a locking ring located between the other flange and the corner of the drum extension to hold the shell in place.

l i. An engine starter drive including a r0- tatable shaft mounted for longitudinal and rotary movements, a driving member loosely mounted on the shaft and adapted to engage a member of the engine to be started, a control member mounted on the shaft for longitudinal movement thereof and rotary movement therewith, and a friction clutch interposed between the control member and the driving member, said clutch comprising two sets of plates, one. set being interlocked with the driving member, and the control member having a drum extension with which the other set of plates is interlocked, a shell fitting over the drum extension and having flanges at opposite ends, one flange holding the clutch plates in position. and aY locking ring located between the other flange and the corner of the drum extension to hold the shell in place, said ring being a split ring with one end offset to bear against such drum extension.

l5. An engine starter drive including a rotatable shaft, a sleevemounted thereon for longitudinal movementthereof and rotary movement therewith, a stop onthe sleeve, a pinion looselyT mounted on the sleeve and positioned against the stop, a control member mounted on the sleeve for longitudinal movement thereof and rotary movement therewith, a friction clutch interposed between the pinion and control member and mounted thereon,- and manually operated means for shifting the sleeve longitudinally of the shaft.

16. An engine starter drive including a rotatable shaft, a sleeve mounted thereon for longitudinal movement thereof and rotary movement therewith, a stop on the' sleeve, a pinion loosely mounted on the sleeve and ositioned against the stop, a control mem )er mounted on the sleeve for longitudinal move-v ment. thereof and rotary movement theref with, and a friction clutch composed of'plates in two sets, one set being interlocled with the pinion and the other set with the control member, and manually operated means for shifting the sleeve longitudinally of the shaft.

17. An engine starter drive including a rotatable shaft mounted for longitudinal and lrotary movements, a pinion loosely mounted on and normally positioned at one end of the shaft and having longitudinally extending tongues and grooves at one end, a nut threaded on the shaft for longitudinal movement thereof and rotary movement therewith, and a friction clutch composed of plates in two sets, oney set being connected with the nut and the other set having a bore with corresponding tongues andgrooves interlocking with the first mentioned tongues and grooves in combination with manually operated means for moving such shaft longitudinally.

18. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements, a pinion loosely mounted on and normally positioned at one end of the iicient locking device which also holds the parts together to prevent rattle and which permits of easy assembly and disassembly.

I claim:

1. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements, a driving member loosely mounted on the shaft and adapted to engage a member of the engine to be started, a control member mounted on the shaft for longitudinal movement thereof and rotary movement therewith, yielding means constantlyv urging the control member towards the driving member, and a friction clutch interposed between the control member and the driving member.

2. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements, a driving member loosely mounted on the shaft and adapted to engage a member of the engine to be started, a control member threaded upon the shaft for longitudinal movement thereof and rotary movement therewith, yielding means constantly urging the control member towards the driving member, and a friction clutch interposed between the control member and the driving member.

3. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements, a driving` member loosely mounted on the shaft and adapted to engage a member of the engine to be started, a control member threaded upon the shaft for longitudinal movement thereof and rotary movement therewith, a spring constantly' urging the control member towards the driving member. and a friction clutch interposed between the control member and the driving member.

Ll. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements, a driving member loosely mounted on the shaft and adapted to engage ak member of the-engine to be started, a control member threaded upon the shaft for longitudinal movement thereof and rotary movement therewith, a spring constantly urging the control member towards the driving member, and a friction clutch interposed between the control member and the driving member said shaft having a thread such that relative longitudinal movement of such shaft and control member causes a rotary movement of such control member.

5. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements and having a fixed abutm'ent. a driving member loosely mounted on the shaft and adapted to engage a member of the engine to be started, a control member threaded upon the Y shaft for "longitudinal movement thereof and rotary movement therewith, a compression spring interposed between the control member and the fixed abutment on the shaft, and a frictionclutch positioned between the control member and the driving member.

6. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements, a driving member loosely mounted on the shaft and adapted to engage a member of the engine to be started, a con` trol member mounted on the shaft for longitudinal movement thereof and rotary movement therewith, and a frictionclutch .be-l tween the control member and the drivmgV member, the control member cooperating with the clutch to build up a frictional resist' ance sufficient to transmit driving torque to the driving member when such shaft is the drivmg element and to release the clutch Awhen the engine is started and the driving and a frictional clutch between the control member and the driving member, the control member cooperating with the clutch to build up a frictional resistance suflicient to transmit driving torque to the driving member when such shaft is the driving element and to release the clutch when the engine is started and the driving member becomes the driver.

8. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements, a driving member loosely mounted on the shaft and adapted to engage a member of the engine to be started, a con trol member mounted on the shaft for longitudinal movement thereof and rotary movement therewith, and a friction clutch interposed between tlie control member andthe driving member, said clutch having members cooperating with the driving member and control member respectively.

9. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements, a driving member loosely mountedon the shaft and adapted to engage a member of the engine to be started, a control member mounted on the shaft for longitudinal movement thereof and rotary movement therewith, and a friction clutch interposed between the control member and the driving member,.said clutch comprising two sets of plates one set having tongue and groove connection with the driving member and the other set having tongue and groove connection' with the control member.

10. An engine starter drive including a rotatable shaft, mounted for longitudinal and rotary movements, a driving member loosely shaft and having longitudinally extending tongues and grooves at one end, a nut threaded on lthe shaft for longitudinal movement thereof and rotary movement therewith, and a friction clutch composed of plates in two sets, one set being connected with the nut and the other set having a bore with corresponding tongues and grooves interlocking with the first mentioned tongues and grooves, and means for detachably holding said other set of plates upon the pinion in combination with manually operated means for moving such shaft longitudinally.

19. An engine starter drive including a ro` tatable shaft mounted forlongitudinal and rotary'movements, a pinion loosely mounted on and normally positioned at one end of the shaft and having longitudinally extending tongues and grooves at one end, a nut threaded on the shaft for longitudinal movement thereof and rotaryT movement therewith and having an extension provided with tongues and grooves, and a friction clutch composed of plates in two sets, one set being interlocked with thetongues and grooves of the pinion and the other set being interlocked with the tongues and grooves of said extension in combination with manually operated means for movingA such shaft longitudinally.

20. An engine starter drive including a rotatable shaft mounted for longitudinal land rotary movements, a pinion loosely mounted on and normally positioned at one end of the shaft and having longitudinally extending tongues and grooves at one end, a nut threaded on the shaft for longitudinal movement thereof and rotary movement therewith, saidk nut having a drum portion, and a friction clutch composed of plates in two sets, one set being interlocked with the tongues and grooves of the pinion and the otherset being interlocked with the drum in combination with manually operated means for moving such shaft longitudinally.

21. An engine starter drive including a rotatable shaft, a sleeve mounted thereon for longitudinal movement thereof and rotary movement therewitlna stop on the sleeve, a

pinion loosely mounted on the sleeve and positioned against the stop, a control mem er mounted on the sleeve for longitudinal movement thereof and rotary movement therewith, a friction clutch interposed between the pinion and control member and mounted thereon, and manually operated means for shifting the sleeve longitudinally of the shaft, including a shipper sleeve slidable on the shaft and made separate from, but attachable to the drive sleeve.

- a member of the engine to be started, a control member mounted on the shaft for longiated with the controlmember for the iconve'rsion of the longitudinal movementofv the shaft into rotary movement ofthe control member and the driving member in event "of abutting of the driving member and'elngine member.

23. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements, a. driving 'member loosely mounted on the shaft and adapted to enf gage a member of the engine to be started, a

control member mounted on the shaft for longitudinal movement thereof and rotary movement therewith, and operatively connected with the driving member, and means associated with the control member for the conversion of the longitudinal movement of the shaft into rotary movement of the control member and the driving member in event-of abutting of the driving member and engine member, said means including a screw thread connection between the control member and the shaft. l

24. An engine starter drive including a rotatable shaft mounted for longitudinal and rotary movements, a driving member loosely mounted on the shaft and adapted to .engage a member of the `engine to be started,v a control member mounted on the shaft for longitudinalmovement thereofand rotary movement therewith,l and operatively connected with the driving member, and means associated -with the vcontrol member for the conversion of the longitudinal movement of the shaft into rotary movement of the control member and the driving member in event-of member towards the driving member.

25. An engine starter drive includinga r-.- tatable shaft mounted for longitudinal and rotary movements, a driving member loosely mounted on the shaft and adapted to engage a member of the engine to be started, a control member mounted on the shaft for longitudinal movement thereof and rotary movement therewith, and operatively connected with the driving member, and means associated with the control member for the conversion of the longitudinal movement of the shaft into rotary movement of the control membery and the driving member in event ofabutting of the driving member and engine member,

and a friction clutch operatively connecting l the controlmemberwith the driving inember. '26; An ,engine starterfdrive unitary assembly adapted tobe slippeduponf formed as 4az adriving shaft and-comprising a :hollowiro-l i-'f tatable shaft adaptedto be driven by su'ch driving shaft, a driving member loosely mounted upon the hollow shaft, a control member mounted upon such hollow shaft for longitudinal movement thereof and rotary movement therewith, operating connection between the driving member` and the control member, and a shipper means at one end of t-he hollow shaft whereby such assembly may be shifted longitudinally.

27. An engine starter drive formed as a unitary assembly adapted to be slipped upon a driving shaft and comprising a hollow rotatable shaft adapted `to be driven by such driving shaft,` a driving member loosely mounted upon the hollow shaft, a control member mounted upon such hollow shaft for longitudinal movement thereof-and rotary movement therewith, a friction clutch forming the operating connection between the driving member and the control member, a stop nut at one end of the hollow shaft adj acent the driving member, and a shlpper de-` vice at the other end thereof adjacent the control member whereby such assembly may be shifted longitudinally.

28. An engine starter drive including a driving member, a control membera friction clutch interposed between and directly cooperating with the driving member and the control member and controlled by the latter, said members and clutchbeing formed as a unit assembly, and a rotatable and longitudinally movable member on which said assembly is mounted to move therewith as a unit. y

29. An engine starter drive including a driving member, a control member, a friction clutch interposed between and directly cooperating with the driving member and the control member and controlled by the latter, said members and clutch being formed as a -unit assembly, a rotatable and longitudinally shiftable member on which said assembly is mounted to move therewith as a unit, and a shaft member operatively connected with the last said member to rotate it and permit its longitudinal shifting movement.

30. An engine starter drive including a driving shaft, a driving member mounted for rotary movement and for longitudinal movement, a control member adapted to cooperate with the driving member and threaded on said shaft for rotary movement and for longitudinal movement, yielding means for urging the control member towards the driving member, and a torque transmitting device interposed between the control member and the drlvlngmember and controlled by said control'member for one-Way torque transmis-4 sion. .l l

31. An engine sta-rter driv' including a rotatable shaft mounted for longitudinal and rotary movements', a.` driving member loosely mounted on'the shaft and adapted to engage a. member of the engine to be started, a control member threaded on the shaft for longitudinal movement thereof and rotary movement therewith, yielding means constantly urging the control member towards the driving member, and a torque transmitting device interposed between the control member and the driving member and controlled by said control member for one-way torque transmiss1on.

32.1An engine starter drive including a driving member, a control member, afriction clutch interposed between and directly cooperating with the driving member and the control member and controlled by the latter,` said members and clutch being formed as a unit assembly,a rotatable and longitudinally movable member on which said assembly is mounted to move therewith as a unit. and means for actuating said control member to vary the torque-carrying capacity of said clutch.

33. An engine starter drive including a driving member, a control member, a friction clutch interposed between and directly cooperating with the drivingmember and the control member and controlled by the latter, said members and clutch being formed as a unit assembly, a rotatable and longitudinally movable member on which said assembly is mounted to move therewith as a unit, and means interposed between the last ber and said control member 4for actuating said control member to varyv the torque-carrying capacity of said clutch.

WILLIAM L. MCGRATH.

said mem- 

